<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <div class="box">
        <div class="content"></div>
    </div>
</body>
<style>
    *{
        margin: 0px;
        padding: 0px;
    }
    .box{
        width: 1200px;
        height: 800px;
        display: flex;
        justify-content: center;
        align-items: center;
    }
    .content{
        width: 300px;
        height: 200px;
        background-color: blue;
        animation: dh;
        animation-duration: 2s;
    }
    @keyframes dh {
        0%{
            background-color: chocolate;

        }
        30%{
            transform: scale(2);
            background-color: crimson;
        }
        60%{
            transform: scale(1);
            background-color: darkmagenta;
        }
        100%{
            background-color: black;
        }
    }
</style>
</html>